Of vital importance is the need to invest in research and technology, prepare governments and local authorities including with realistic exercise scenarios, understand how to protect diverse populations with varying needs including the most vulnerable in society, and provide clear and transparent information and advice to the public.

"A big lesson was that we need more long-term planning on how we can spot, track and ultimately mitigate potentially dangerous asteroids," says Detlef Koschny, Head of ESA's Planetary Defence Office.

"Simply thinking in annual or bi-annual planning cycles, which is how many budgets at public institutions are set, is not good enough to address a risk that has been hundreds of millions of years in the making."

Finally, one thing is clear: an asteroid impact, although unlikely, is probably going to happen sooner or later – so it is best to be prepared.